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Assertion (A):
The walls of bacterial cells are treated with lysozyme to release the genetic material (DNA).
Reason (R):
Plant cells require treatment with cellulase, and fungal cells require chitinase to break down their respective cell wall structures for DNA isolation.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
Ligation of foreign DNA at the $Pst$ I site of pBR322 causes insertional inactivation, leading to the loss of tetracycline resistance.
Reason (R):
The general principle of insertional inactivation is that the foreign DNA is inserted within the coding sequence of an antibiotic resistance gene, making it non-functional.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
Ever since the seventeenth century, the whole approach to understanding natural phenomena became anthropocentric.
Reason (R):
The focus of human knowledge, particularly in physics and chemistry, was directed toward developing technologies that add to the comfort and welfare of human lives.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
Asexual reproduction preserves genetic information efficiently.
Reason (R):
Sexual reproduction provides opportunities for variation and the formulation of unique combinations of genetic setups, some of which may be beneficial.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
The first artificial recombinant DNA was constructed in vitro by linking an antibiotic resistance gene with a native plasmid of Salmonella typhimurium.
Reason (R):
This linking process was achieved by the enzyme DNA ligase, which acts on cut DNA molecules and joins their ends.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
Maintenance of the introduced DNA in the host and its transfer to the progeny is the final basic step in genetically modifying an organism.
Reason (R):
The first basic step in genetic modification is the identification of DNA with desirable genes.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
The enzyme that cuts DNA, known as restriction endonuclease, was isolated in 1963.
Reason (R):
This restriction enzyme was one of two enzymes responsible for restricting the growth of bacteriophage in Escherichia coli.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
The first restriction endonuclease, Hind II, was found to always cut DNA molecules at a particular point by recognising a specific sequence of six base pairs.
Reason (R):
The recognition sequence of Hind II is a specific DNA nucleotide sequence on which its functioning depends.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
In the restriction enzyme name $EcoRI$, the Roman number 'I' indicates the order in which the enzyme was isolated from that strain of bacteria.
Reason (R):
The letter 'R' in $EcoRI$ is derived from the genus of the prokaryotic cell from which it was isolated.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
Exonucleases remove nucleotides from the ends of the DNA strand.
Reason (R):
Endonucleases make cuts at specific positions within the DNA.
[Biotechnology-Principles-and-Processes] [class-xii ]
This Page Score: 0/40